Can't write and save a video file using OpenCV and Python

Question

I'm trying to process frames from a video stream, and it as a new video.

This is what I'm doing :

fourcc = cv2.VideoWriter_fourcc(*'XVID') out = cv2.VideoWriter('Videos/output.mp4',fourcc, fps, (1080,1080)) 

I keep getting :

OpenCV: FFMPEG: tag 0x44495658/'XVID' is not supported with codec id 13 and format 'mp4 / MP4 (MPEG-4 Part 14)' OpenCV: FFMPEG: fallback to use tag 0x00000020/' ???' 

I think I'm using the wrong fourcc value... Which one should I use ? I've been trying a lot of them.

I'm using Ubuntu 16.04, Python 2.7.11 and OpenCV 3.1.0

Answer 1

Define the codec and create VideoWriter object like this

fourcc = cv2.VideoWriter_fourcc(*'MPEG') out = cv2.VideoWriter('output.avi',fourcc, 20.0, (640,480)) 

Answer 2

For Windows users

I am using OpenCV 2 with Python 3.6, on Windows 10.

The 'XVID' codec, along with producing a .avi file, seems to be the most generic solution (if not the only one that works).

fourcc = cv.VideoWriter_fourcc(*'XVID') out = cv.VideoWriter('test.avi', fourcc, 60, (320, 240)) 

In addition, only BGR can be directly written with such a VideoWriter declaration. Don't try to write gray frames: the output would be empty.